Downscaling ferroelectric field effect transistors by using ferroelectric Si-doped HfO2

Throughout the 22 nm technology node HfO₂ is established as a reliable gate dielectric in contemporary complementary metal oxide semiconductor (CMOS) technology. The working principle of ferroelectric field effect transistors FeFET has also been demonstrated for some time, for dielectric materials like PZT and SrBi₂Ta₂O₉. However, integrating these into contemporary downscaled CMOS technology nodes is not trivial due to the necessity of an extremely thick gate stack. Recent developments have shown HfO₂ to have ferroelectric properties given the proper doping. Moreover, these doped HfO₂ thin films only require layer thicknesses similar to the ones already in use in CMOS technology. This work will show how the incorporation of Si induces ferroelectricity in HfO₂ based capacitor structures and finally demonstrate non-volatile storage in nFeFETs down to a gate length of 100 nm.